ASTM F2413-24 is the U.S. consensus performance standard for protective (safety-toe) footwear, with toe impact rated at 50 ft·lbf (≈67.7 J) and compression at 2,500 lbf (≈11.1 kN) for the I/75/C/75 designation [S1][S3].
OSHA 29 CFR 1910.136 sets the U.S. legal duty: employers must ensure workers wear protective footwear that meets (or is at least as effective as) one of the listed consensus standards when foot hazards are present [S2][S3].
In Europe, the split is sharper: EN ISO 20345 covers safety footwear with a toe cap resisting 200 J impact and 15 kN compression, while EN ISO 20347 covers occupational footwear with no mandatory toe cap and lower mechanical thresholds [S4][S6].
Where each standard actually applies
ASTM F2413-24 is the performance specification; the companion standard ASTM F2412 defines the test methods (impact, compression, puncture, metatarsal, electrical hazard, static dissipative, heat, cold) used to certify F2413 compliance [S1][S3]. Footwear labeled "ASTM F2413-18" or "ASTM F2413-24" is OSHA-accepted for U.S. workplaces [S3]. ASTM F3445-21, by contrast, covers slip resistance only and is not recognized by OSHA [S3].
EN ISO 20345 (safety footwear) and EN ISO 20347 (occupational footwear) are the two parallel European standards. 20345 mandates a safety toe cap rated to 200 J impact and 15 kN compression, with sub-classes SB, S1, S1P, S2, S3, S4, and S5 [S4]. 20347 covers occupational shoes without a mandatory toe cap, with classes OB, O1, O2, and O3 stepping up slip resistance, antistatic behaviour, energy absorption in the heel, water resistance, and puncture resistance [S4][S6].
OSHA 29 CFR 1910.136 is the only U.S. federal regulation in this set. It does not name a brand or a test value: it requires the footwear to comply with consensus standards such as ASTM F2413, or to be "at least as effective," and it leaves the hazard assessment to the employer [S2][S3].
Mechanical thresholds side by side
U.S. safety-toe boots under ASTM F2413-24 must pass the I/75 impact test (50 ft·lbf / 67.7 J) and the C/75 compression test (2,500 lbf / 11.1 kN) at the toe [S1]. European EN ISO 20345 S-class boots must survive 200 J impact and 15 kN compression at the toe cap [S4]. Footwear certified to UNE-EN ISO 20345 SB requires a protective toe cap rated for at least 200 J impact and 15 kN compression, which differs from the requirements defined by ASTM F2413, so an SB boot is not automatically a 1:1 swap for an ASTM-rated product without checking the test data.
Optional add-ons differ in the two systems. ASTM F2413 lets the manufacturer add module codes for metatarsal (Mt), puncture (PR), electrical hazard (EH), static dissipative (SD), conductive (CD), and chain-saw cut resistance [S1][S3]. EN ISO 20345 builds puncture protection, antistatic behaviour, heat/cold insulation, and water resistance into the S1–S5 ladder instead of tacking them on as suffixes [S4].
Who each category is actually for
Safety footwear (EN ISO 20345) is for jobs with falling-object, crush, or puncture risk: construction, warehousing, logistics, metallurgy, heavy manufacturing [S4]. In the U.S., this maps to OSHA's hazard assessment under 1910.136: warehouse operations, heavy-equipment moving, large-animal handling, and certain chemical jobs trigger the ASTM F2413 requirement [S2][S5].
Occupational footwear (EN ISO 20347) is for lower-risk environments: hospitality, healthcare, cleaning, retail, light logistics. The priority is slip resistance, antistatic behaviour, energy-absorbing heel, and all-day comfort, with no certified toe cap [S4][S6]. In the U.S., the equivalent is "closed-toe, closed-heel" work shoes specified for labs, food service, and administrative areas, where ASTM F2413 is not required [S5].
General work footwear, distinct from both safety and occupational PPE, is unregulated from a foot-protection standpoint and is chosen for comfort, slip resistance, and minor abrasion only. The protective role of any of these categories is a backstop, never a substitute for safe handling and material-handling equipment [S5].
Selection criteria that decide the class
Run a documented hazard assessment first. OSHA 1910.136 explicitly conditions the footwear requirement on the presence of foot hazards identified by the employer [S2][S3]. Mizzou EHS repeats the same logic: "the area supervisor, using EHS as the hazard assessment resource, will determine appropriate protective footwear" [S5].
Then match the hazard to a class. Falling or rolling objects, sharp debris, and heavy loads push the job into safety footwear (ASTM F2413 I/75/C/75, or EN ISO 20345 S3 for added puncture and tread). Slippery floors with no impact risk fit occupational footwear (EN ISO 20347 O2/O3, or ASTM F3445-21 slip-only where specified). Electrical work adds the EH module under ASTM or antistatic/insulating variants under 20345/20347 [S1][S3][S4][S5].
For trade-offs, see fire-safety PPE selection for the broader PPE ladder this footwear sits on, and PPE inspection and testing apparatus for the equipment used to verify impact, compression, and slip performance on a delivered lot.
Limits, failure modes, and compliance gaps
OSHA does not certify individual boots, it enforces the employer's program. Citation risk falls on the employer if a hazard assessment is missing or the supplied footwear does not meet ASTM F2413 [S2][S3]. Mizzou EHS calls out the second common failure: a single toe cap does not protect the metatarsal, the sole, or the ankle, and a "safety-toe" boot is not a general-purpose PPE solution [S5].
EN ISO 20347 occupational shoes have no certified toe cap. Wearing them in a zone with documented falling-object risk violates the European risk-assessment flow and the U.S. 1910.136 duty alike, even though the shoes are otherwise comfortable and slip-rated [S4][S6]. Conversely, putting a heavy 20345 S3 boot on a hospital orderly adds fatigue and slip-fall risk on smooth indoor floors that an O2/O3 shoe handles better [S4].
ASTM F3445-21 is a slip-only standard that OSHA does not recognize. Marking a boot "F3445-21" does not satisfy 1910.136 for impact or compression, and an F3445-only shoe is not interchangeable with an F2413 I/75/C/75 boot on a construction site [S3].
Sourcing signals and traceability
When procuring, demand the exact citation: "ASTM F2413-24, I/75/C/75, Mt/75, PR, EH" or "EN ISO 20345:2022 S3 SR HRO" written on the product data sheet, not just a generic "safety-rated" label [S1][S3][S4]. For European occupational orders, require the EN ISO 20347 class code (OB/O1/O2/O3) plus the slip-resistance suffix (SR) and any antistatic, heat, or cold insulation code [S4][S6].
Track lot-level test reports. ASTM F2412 test reports and EN ISO 20344 / 20345 / 20347 lab certificates should be available per shipment, especially for EH-rated and chain-saw-cut-resistant lines, where dielectric and cut-test results vary by production batch [S1][S3]. For construction PPE programs and PPE handling on sites with heavy equipment, the PPE inspection routine is the practical check between warehouse and worker.
Two trackable signals for the next sourcing cycle: (1) confirm whether your supplier's 2026 catalogue still cites F2413-18 or has rolled to F2413-24, since the revision year changes the label but not the impact and compression numbers [S1][S3]; (2) for cross-border shipments, ask whether the European CE marking references EN ISO 20345:2022 or an earlier amendment, because the 2022 revision tightened several test methods and slip-resistance criteria [S4][S6].
For related coverage, see Load-Break Switch Rated Making and Breaking Capacity: Spec Boundaries and 2026 Sourcing.